Cleaning heads (often called pop-up cleaning heads or in-floor cleaning system heads) are small nozzles installed flush into the floor and sometimes the walls or steps of a swimming pool. When the pool's pump cycles water through them, hydraulic pressure pushes each head up out of its housing and shoots a powerful jet of water across the pool surface in a fixed direction. As they cycle on and off in groups, the jets sweep dirt, leaves, and debris toward the main drain, where it gets pulled into the filtration system.
When the water flow stops or moves to the next zone, the heads retract back down flush with the pool floor, so you don't feel them underfoot or see them as obstacles.
